The superfast blue star probably formed when two smaller stars merged. Image: NASA
A blue star hurtling through the outer reaches of our galaxy originated in the centre of the Milky Way 100 million years ago.
So say astronomers at the Harvard-Smithsonian Centre for Astrophysics in the US, who compared the star’s position with background galaxies in Hubble Space Telescope observations. Of the 16 known hypervelocity stars, which are moving fast enough to eventually escape the Milky Way, this is the only star the origin of which is known.
Understanding the movement of these stars could contribute to our knowledge of dark matter, whose gravity affects stars’ trajectory.
